Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) is an important pest of stored products. Insecticidal treatment is a common practice for the control of this notorious insect pest. Most studies are focused on the immediate and/or delayed mortality effects. while there are no data on the effects of insecticides on the population fitness. https://parisnaturalfoodes.shop/product-category/magnetic-washball/